Container group delivery mechanism, and equipment and method for transporting container

ABSTRACT

An air conveyer receives an uppermost container group elevated by a lift device and transporting the container group horizontally. A pushing device is provided for pushing the uppermost container group onto the adjacent airflow conveyer by contacting the container group at one side thereof and moving horizontally toward the other side. A forward-fall preventive device is provided to be switchable between a closed state for lying forwardly in a pushing direction of the container group, as the pushing device moves horizontally, to be capable of preventing a forward fall of containers, and an open state for opening a forward position in the pushing direction of the container group when the container group rides the airflow conveyer to enable a discharge of the container group. A speed varying mechanism is provided for varying a relative speed between a transport speed of the airflow conveyer and a pushing speed of the pushing device.

TECHNICAL FIELD

The present invention relates to a container group transfer mechanismhaving a pushing device for horizontally pushing a container groupincluding a plurality of standing containers arranged and collected in ahorizontal direction, by contacting the container group at one sidethereof and moving horizontally toward the other side, and aforward-fall preventive device switchable between a closed state forcontacting a forward end in a pushing direction of the container groupto be capable of preventing a forward fall of the containers by lying atthe forward end in the pushing direction of the container group as thepushing device moves horizontally, and an open state for opening aforward position in the pushing direction of the container group toenable a discharge of the container group, and relates also to containertransporting equipment having such a container group transfer mechanism.

Such container transporting equipment includes a lift device forvertically stacking in stages a plurality of container groups eachincluding a plurality of standing containers arranged and collected in ahorizontal direction, and carrying and elevating, stage by stage, theplurality of container groups stacked vertically, a conveyer disposedadjacent this lift device for receiving an uppermost container groupelevated by the lift device and transporting the container grouphorizontally, and a container group transfer mechanism having a pushingdevice for pushing the uppermost container group onto the conveyer bycontacting the container group at one side thereof and movinghorizontally toward the other side, and a forward-fall preventive deviceswitchable between a closed state for lying forwardly in a pushingdirection of the container group, as the pushing device moveshorizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of the container group when the container group ridesthe conveyer to enable a discharge of the container group.

Further, the invention relates also to a method for use with such acontainer group transfer mechanism and container transporting equipment.

BACKGROUND ART

In a production process of beverages such as beer and soft drinks, forexample, containers of the beverages are delivered on pallets andremoved from the pallets stage by stage. A plurality of containers aretransported as groups. As shown in FIG. 16, a funnel-like single rowtransport path ultimately turns the containers into a single row for afilling machine to fill the contents. Equipment for transporting suchcontainers from pallets vertically stacks in stages a plurality ofcontainer groups each including a plurality of standing containersarranged and collected in a horizontal direction, carries and elevates,stage by stage, the plurality of container groups stacked vertically bymeans of a lift device, receives an uppermost container group elevatedby the lift device, moves the group horizontally by a pushing deviceonto an adjacent airflow conveyer, switches a forward-fall preventivedevice to an open state to discharge the container group onto theairflow conveyer, and transports the discharged containers by theairflow conveyer to a next process. The movement from the lift device tothe airflow conveyer is executed by what is known as a container grouptransfer mechanism.

As shown in FIGS. 19 and 20, for example, this type of container grouptransfer mechanism 2 conventionally employs a construction having aframe 190 a with props 190 b erected thereon, and a forward-fallpreventive device 24 having arms 191 a disposed at opposite ends thereofand pivotally supported by the props 190 b, whereby the forward-fallpreventive device 24 is vertically pivotable to open and close.

[First Problem to be Solved by the Invention]

According to the container group transfer mechanism constructed to bevertical pivotable to open and close, a container group 4 may be movedreliably from the pallet to the conveyer. However, it is necessary tosecure a space for movement of the props 190 b occurring with thehorizontal movement of the container group transfer mechanism 2, and aretraction space for allowing the forward-fall preventive device 24 toretract forwardly and above the container group transfer mechanism 2when switched to the open state for discharging the container group.

Currently, in the beverage production process, the container transportis effected at high speed and various containers are transported. Thecontainers tumble or become damaged on the conveyer. However, theconventional container group transfer mechanism 2 has problems not onlythat it is impossible to accommodate, in a space above said receivingdevice, for example, a monitoring instrument for monitoring a state ofthe container group transferred to said receiving device, or a device ofdifferent function such as a container tumbling preventive mechanism,but that it is impossible to use a conveyer such as an airflow conveyerhaving an upper guide for tumble preventing purposes.

A first object of the present invention is to provide a container grouptransfer mechanism capable of allowing, for example, a monitoringinstrument or a device of different function such as a containertumbling preventive mechanism to be disposed in a space above thecontainer group transfer mechanism, or capable of using containertransporting equipment with a tumbling preventive upper guide, andcontainer transporting equipment.

[Second Problem to be Solved by the Invention]

In the container transporting equipment which receives, in the containergroup transfer mechanism, the uppermost container group elevated by saidlift device, transports it onto the adjacent conveyer by horizontalmovement, discharges said container group onto said conveyer by openingthe forward-fall preventive device, thereafter moves said containergroup transfer mechanism back onto said lift, and repeats the aboveprocess again to receive a next container group, where an arrangement isemployed to receive the next container group after moving said containergroup transfer mechanism back onto said lift device and closing theforward-fall preventive device, the time until said forward-fallpreventive device is closed and the time from the closure of saidforward-fall preventive device until the next container group isreceived are required separately, thus a long time is taken to receivethe container group, resulting in a low container transportingefficiency.

Then, where an arrangement is employed to receive the next container bythe time said forward-fall preventive device is closed, the closure ofsaid forward-fall preventive device and reception of the next containergroup may be carried out simultaneously to shorten the time taken toreceive the container group and to improve the container transportingefficiency container. At this time, however, there occurs a risk that,when an operation is performed to close said forward-fall preventivedevice, said forward-fall preventive device swings to excess underinertia, instead of stopping in home position, and strikes, with impact,the container received in said container group transfer mechanism,thereby damaging said containers.

A second object of the present invention is to employs a container grouptransfer mechanism in which said forward-fall preventive device does notmove upward, in order to eliminate the above problem and improve thecontainer transporting efficiency, and to provide a container grouptransfer mechanism which, even where an arrangement is employed toreceive next containers by the time the forward-fall preventive deviceis closed, reduces the force of inertia acting on the forward-fallpreventive device in a closing operation to decrease the impact ofcontact with the containers, thereby to check damage to the containers.

[Third Problem to be Solved by the Invention]

Conventionally, the forward-fall preventive device needs to behave inopening or closing time such that containers that tumble easily aretransported by deliberately maintaining the contact with the pushingdevice as far as the airflow conveyer to avoid scattering during thetransport, and that containers vulnerable to damage are transported in arather loose state to check damage by minimizing the pressure of contactamong the containers or by the pushing device. However, there is nomethod for controlling this. An apparatus or method having transportfunctions corresponding to such transport modes has not been developed.

A third object of the present invention, therefore, is to providecontainer transporting equipment and a container transporting methodhaving transport functions corresponding to transport modes forcontrolling a pushing speed of the pushing device for pushing containergroups out onto the airflow conveyer, in relation to a containertransport speed of the airflow conveyer, thereby to solve the aboveproblem.

DISCLOSURE OF THE INVENTION

[Means for Solving the First Problem]

[Construction]

In certain embodiments, the present invention, e.g., as illustrated inFIGS. 1 and 4 to 11, is characterized by a container group transfermechanism comprising a pushing device 23 for horizontally pushing acontainer group 4 including a plurality of standing containers arrangedand collected in a horizontal direction, by contacting said containergroup 4 at one side thereof and moving horizontally toward the otherside, and a forward-fall preventive device 24 for contacting a forwardend in a pushing direction of said container group 4 and switchablebetween a closed state for lying forwardly in the pushing direction ofsaid container group 4, as said pushing device 23 moves horizontally, tobe capable of preventing a forward fall of said containers, and an openstate for opening a forward position in the pushing direction of saidcontainer group 4 to enable a discharge of the container group 4,wherein said forward-fall preventive device 24 is laterally switchable.

In other embodiments, the present invention. e.g. as shown in FIGS. 1 to11, is characterized by container transporting equipment comprising alift device 14 for vertically stacking in stages a plurality ofcontainer groups 4 each including a plurality of standing containersarranged and collected in a horizontal direction, and carrying andelevating, stage by stage, said plurality of container groups 4 stackedvertically, a conveyer 17 disposed adjacent said lift device 14 forreceiving an uppermost container group elevated by said lift device 14and transporting the container group horizontally, and a container grouptransfer mechanism having a pushing device 23 for pushing said uppermostcontainer group 14 onto said conveyer 17 by contacting said containergroup 4 at one side thereof and moving horizontally toward the otherside, and a forward-fall preventive device 24 switchable between aclosed state for lying forwardly in a pushing direction of saidcontainer group 4, as said pushing device 23 moves horizontally, to becapable of preventing a forward fall of said containers, and an openstate for opening a forward position in the pushing direction of saidcontainer group when said container group 4 rides said conveyer 17 toenable a discharge of said container group 4, wherein said forward-fallpreventive device 24 is laterally switchable.

In other embodiments, such as illustrated in FIGS. 12 and 13, thepresent invention is characterized in that said conveyer 17 is anairflow conveyer 12.

Certain embodiments. e.g., as illustrated in FIGS. 1 and 4 to 11, arecharacterized by a container group transfer method comprisinghorizontally pushing, with a pushing device, a container group includinga plurality of standing containers arranged and collected in ahorizontal direction, by contacting said container group at one sidethereof and moving horizontally toward the other side, and dischargingthe container group by opening a forward-fall preventive device forcontacting a forward end in a pushing direction of said container groupand switchable between a closed state for lying forwardly in the pushingdirection of said container group, as said pushing device moveshorizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of said container group to enable a discharge of thecontainer group, in which said container group is discharged bylaterally opening said forward-fall preventive device.

Other embodiments. e.g. such as illustrated in FIGS. 1 to 11, arecharacterized by a container group transporting method comprisingvertically stacking in stages a plurality of container groups eachincluding a plurality of standing containers arranged and collected in ahorizontal direction, and carrying and elevating, stage by stage, with alift device, said plurality of container groups stacked vertically,horizontally pushing, with a pushing device, an uppermost containergroup elevated by said lift device by contacting said container group atone side thereof and moving horizontally toward the other side to pushsaid container group onto a conveyer disposed adjacent said lift devicefor receiving said uppermost container group and transporting thecontainer group horizontally, and discharging said container group byopening a forward-fall preventive device switchable between a closedstate for lying forwardly in a pushing direction of said containergroup, as said pushing device moves horizontally, to be capable ofpreventing a forward fall of said containers, and an open state foropening a forward position in the pushing direction of said containergroup when said container group rides said conveyer to enable adischarge of said container group, in which said container group isdischarged by laterally opening said forward-fall preventive device.

The invention as illustrated in FIGS. 12 and 13, is characterized inthat the conveyer is an airflow conveyer.

While reference numbers are set out as above for expediency ofcomparison to the drawings, such entry does not limit the presentinvention to the constructions shown in the accompanying drawings.

[Functions and Effects]

In certain embodiments said forward-fall preventive device is laterallyopenable and closable to allow an effective use of the forward and upperspaces of the container group transfer mechanism. The term laterallyherein indicates a direction perpendicular to both the upstandingdirection of the containers (front-to-back direction relative to theplane of FIGS. 10 and 11) and the pushing direction (direction of arrowsin FIGS. 10 and 11). The term forward indicates forward in said pushingdirection (direction of the arrow in FIG. 10). The term upper spaceindicates a space opposite from the conveyor.

Where, as in the prior art, the forward-fall preventive device isvertically openable and closable by pivotal movement of the armspivotally supported by the props, it is necessary to secure a space formovement of the props occurring with the horizontal movement of thecontainer group transfer mechanism, and a retraction space for allowingthe forward-fall preventive device to retract forwardly and above thecontainer group transfer mechanism when switched to the open state fordischarging a container group. A tall container group in particularrequires the forward-fall preventive device to be raised to a height forallowing said container group to be discharged, and a large space to besecured for the forward-fall preventive device to retract forwardly andabove the container group transfer mechanism. However, where, as in theinstant case, the forward-fall preventive device is laterally openableand closable, a retraction space is not required for the forward-fallpreventive device to retract forwardly and above the container grouptransfer mechanism. Thus, the container group transfer mechanism may bedisposed in a location having a limited upper space. It is also possibleto accommodate, in a space forwardly of and above the container grouptransfer mechanism, for example, a monitoring instrument or a device ofdifferent function such as a container tumbling preventive mechanism.

As a result, the container group transfer mechanism of the presentinvention improves the degree of freedom of upper space designing, andcan cope with a speedup and diversification of container transport. Thismechanism may easily be introduced into existing container transportingequipment.

In some embodiments, the container transporting equipment has saidforward-fall preventive device laterally switchable. It is thereforepossible to accommodate a monitoring instrument or a container tumblingpreventive mechanism in a space forwardly of and above the receivingportion.

That is, after the container group transfer mechanism pushes andtransfers the uppermost container group elevated by the lift device,onto the receiving portion of the conveyer, the forward-fall preventivedevice may be switched to the open state to open a forward region in thepushing direction of the container group for discharging the containergroup. Since the forward-fall preventive device is opened laterally, atransport region is not required above the receiving portion forretracting the forward-fall preventive device. Thus, the containertransporting equipment having the container group transfer mechanism maybe installed in a location having a limited upward space. It is alsopossible to accommodate, in a space above said receiving portion, forexample, a monitoring instrument or a device of different function suchas a container tumbling preventive mechanism for monitoring presence ofdamage to or tumbling of the container group transferred to thereceiving portion or for preventing tumbling in time of transfer.

As a result, the container transporting equipment has improvedfunctionality to realize smooth transport.

According to certain embodiments of the invention, the conveyer adjacentsaid lift device need not employ a mechanical conveyer, but may use anairflow conveyer for transporting the containers by means of air. Thusthe problems of the mechanical conveyer may be solved.

Conventionally, a mechanical conveyer is employed as the conveyer. Themechanical conveyer transports containers as placed on an endlessrotating member, by frictional contact between the endless rotatingmember and container bottoms. Thus, there is a limitation to itstransport speed for tumble-free transport. Fast transport is impossible.

For a feeding mechanism disposed in a downstream position forconstricting a transport path to rearrange containers in containergroups into a row to feed the cans without interruption to a nextprocess, the lift device may elevate a plurality of container groupsplaced on a pallet, stage by stage, with the container group transfermechanism transferring the container groups to the adjacent receivingportion of the conveyer. In such a construction, in order to cover anon-feed time after transferring a lowermost container on a pallet tothe receiving portion until discharging the pallet and transferring anuppermost container on a next pallet to the receiving portion, asufficient number of containers to be discharged from said feedingmechanism within said non-feed time must be stored on the conveyer ortransport speed must be increased to prevent an interruption of thecontainers. However, the mechanical conveyer cannot increase itstransport speed for transporting the containers, and the conveyer musthave an increased length to store a sufficient number of containers forcovering the non-feed time. Thus, the conveyer has to be very long.

With an increase in transport speed, the mechanical conveyer employing atransport mode relying on frictional contact would transmit thetransporting force of the endless rotating member directly to aplurality of containers accumulating in said feed mechanism. Anincreased force of contact among the containers could result in damageor collapse.

On the other hand, in the construction of the present invention, aplate-like upper guide or the like may be provided as a tumblepreventing mechanism to extend above and parallel to the conveyer from aspace above the receiving portion to said feed mechanism for contactingthe upper ends of the containers when the containers are about totumble, thereby preventing tumbling. Thus, the airflow conveyer may beemployed for transporting the containers by means of air. This airflowconveyer moves the containers on the conveyer by blowing air thereto. Nofrictional contact takes place between the endless rotating member andcontainer bottoms occurring with the mechanical conveyer. Transportspeed for transporting the container may be increased. Instead ofcovering said no-feed time with the number of containers, the containersmay be supplied to the feed mechanism without interruption by increasingthe transport speed of a next container group. Thus, the conveyer mayhave a reduced length.

In the air flow conveyer, even with increased speed of transportperformed by means of air, a plurality of containers accumulating andcontacting one another in said feed mechanism are free from thefrictional contact between the endless rotating member in rotation andcontainer bottoms occurring with the mechanical conveyer. With an escapeof excess air, no undue force acts on the containers, and hence nochance of damage or collapse.

As a result, the container transporting equipment may be made compact tobe installable in a small space. The containers may also have improvedquality.

[Means for Solving the Second Problem]

[Construction]

As illustrated in FIG. 7, certain embodiments of the invention arecharacterized by a container group transfer mechanism comprising apushing device 23 for horizontally pushing a container group 4 includinga plurality of standing containers arranged and collected in ahorizontal direction, by contacting said container group 4 at one sidethereof and moving horizontally toward the other side, and aforward-fall preventive device 24 for lying forwardly in a pushingdirection of said container group 4, as said pushing device 23 moveshorizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of said container group to enable a discharge of thecontainer group 4, wherein said forward-fall preventive device 24includes turn elements 40 connected for pivotal movement about rotaryshafts 39, rotary drive mechanisms 38 for swinging said turn elements 40within a predetermined angular range, and gate members 41 fixedlysupported by said turn elements for contacting a forward end in apushing direction of said container group 4 to be capable of preventinga forward fall of the containers, said turn elements 40 being formed tohave centers of gravity located closer to said rotary shafts 38 thancenters of gravity of said gate members 41.

In certain embodiments, such as illustrated in FIG. 9, the forward-fallpreventive device includes buffer mechanisms 45 for absorbing inertialswinging of said gate members 41.

In the embodiment illustrated in FIG. 9, the rotary drive mechanisms 38are formed of air cylinders 42.

As illustrated in FIG. 8, certain embodiments of the invention arecharacterized in that said gate members 41 have elastic materials 59provided in positions contactable with the forward end in the pushingdirection of said container group 4.

While reference numbers are set out as above for expediency ofcomparison to the drawings, such entry does not limit the presentinvention to the constructions shown in the accompanying drawings.

[Functions and Effects]

Certain embodiments of the invention are capable of reducing the forceof inertia acting on the turn elements and gate members during a closingoperation.

That is, the force of inertia acting on the turn elements and gatemembers results from a centrifugal force generated about the rotaryshafts acting as support shafts. Thus, the farther away from the rotaryshafts, the greater the force of inertia becomes.

Where, as shown in FIG. 21, one end of each turn element 40 extends to asubstantially middle position in the right and left direction of thecontainer group transfer mechanism 2 and fixedly supports the gatemember 41 substantially equal in length to said turn element 40, thecenters of gravity of the turn elements 40 and the centers of gravity ofthe gate members 41 are located in approximately the same position. Inthe present invention, the turn elements are formed to have centers ofgravity located closer to the rotary shafts than centers of gravity ofsaid gate members. The overall center of gravity of the turn elementsand gate members regarded as integral is closer to said rotary shaftsthan in the typical construction shown in FIG. 21. This produces theeffect of reducing the force of inertia acting on the turn elements andgate members during a closing operation.

As a result, the impact of the gate members contacting the containersmay be reduced to check damage to the containers.

According to certain embodiments of the present invention the impact ofthe gate members contacting the containers may be further reduced.

That is, the buffer mechanisms can absorb the force of inertia acting onthe turn elements and gate members swinging by inertia. This decreasesthe impact of the gate members contacting the containers.

As a result, damage to the containers may be further checked.

In certain embodiments, inexpensive air cylinders may be used.

That is, an air cylinder is incapable of fine controls such as stoppingrotation at a set position as is possible with a servomotor. Where aircylinders used as the rotary drive mechanisms, it is impossible toperform fine controls such as stopping the turn elements and gatemembers in home position when the forward-fall preventive device isclosed. The turn elements and gate member could swing to excess tocontact the containers with impact, thereby damaging the containers.Normally, use of the air cylinders is inappropriate. By forming the turnelements have centers of gravity located closer to the rotary shaftsthan the centers of gravity of the gate members, or providing the buffermechanisms for absorbing inertial swinging of the gate members as theforce of inertia acting on the turn elements and gate members may bedecreased or absorbed. It is therefore possible to use air cylinders asthe rotary drive mechanisms.

As a result, the rotary drive mechansim can employ inexpensive aircylinders, compared with expensive rotary drive mechanisms in the formof servomotors or the like. This realizes a reduction in the cost of theapparatus.

According to certain embodiments, the impact of contact with thecontainers may be absorbed.

That is, where, for example, the gate members are formed of a rigidmaterial such as metal, even though the impact of the gate memberscontacting the containers is decreased, the rigid metallic gate memberstransmit the impact as it is to the containers, which could damage thecontainers. Where, as in the present invention, the gate members haveelastic materials provided in positions contactable with the forward endin the pushing direction of the container group, the impact occurringupon contact with the containers may be absorbed by an elasticdeformation of the elastic materials.

As a result, damage to the containers may be further checked.

[Means for Solving the Third Problem]

[Construction]

The invention, as illustrated in FIG. 4, is characterized by containertransporting equipment comprising a device for vertically stacking instages a plurality of container groups each including a plurality ofstanding containers arranged and collected in a horizontal direction,and carrying and elevating, stage by stage, said plurality of containergroups stacked vertically, an air conveyer 12 disposed adjacent saidlift device for receiving an uppermost container group elevated by saidlift device and transporting the container group horizontally, a pushingdevice 23 for pushing said uppermost container group onto said airflowconveyer 12 by contacting said container group at one side thereof andmoving horizontally toward the other side, and a forward-fall preventivedevice 24 switchable between a closed state for lying forwardly in apushing direction of said container group 4, as said pushing device 23moves horizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of said container group when said container grouprides said airflow conveyer 12 to enable a discharge of said containergroup, wherein said container transporting equipment comprises a speedvarying mechanism 62 for varying a relative speed between a transportspeed of said airflow conveyer 12 and a pushing speed of said pushingdevice.

The invention, as illustrated in FIG. 14, is characterized by comprisinga control device 66 for automatically varying the transport speed ofsaid airflow conveyer 12 and the pushing speed of said pushing device23.

Certain embodiments of the invention are characterized in that thepushing speed of said pushing device is set faster than the transportspeed of said airflow conveyer.

In certain embodiments, the present invention is characterized in that,as said pushing device moves horizontally forward in the pushingdirection on said airflow conveyer, said forward-fall preventive deviceis switched to the open state, and the transport speed of said airflowconveyer is increased the further forward in the direction oftransporting the containers.

As illustrated in FIG. 15, certain embodiments of the present inventionare characterized by container transporting equipment comprising a liftdevice for vertically stacking in stages a plurality of container groups4 each including a plurality of standing containers 3 arranged andcollected in a horizontal direction, and carrying and elevating, stageby stage, said plurality of container groups 4 stacked vertically, anair conveyer 12 disposed adjacent said lift device for receiving anuppermost container group elevated by said lift device and transportingthe container group horizontally, a pushing device 23 for pushing saiduppermost container group 4 onto said airflow conveyer 12 by contactingsaid container group 4 at one side thereof and moving horizontallytoward the other side, and a forward-fall preventive device 24switchable between a closed state for lying forwardly in a pushingdirection of said container group 4, as said pushing device 23 moveshorizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of said container group when said container group 4rides said airflow conveyer 12 to enable a discharge of said containergroup, wherein said container transporting equipment comprises detectingsensors 67 for detecting presence of containers in regions where anopening operation of said forward-fall preventive device 24 takes place,and a control device 68 for maintaining said forward-fall preventivedevice 24 in the closed state when said detecting sensors 67 detect thecontainers present in the regions of opening, even if said containergroup 4 is brought by said pushing device 23 onto said airflow conveyer12, and for switching said forward-fall preventive device 24 to the openstate for discharging said container group 4 when an absence ofcontainers is detected.

Certain embodiments of the present invention are characterized bycomprising an upper guide disposed above said airflow conveyer forcontacting upper ends of the containers to prevent tumbling of thecontainers being transported, said forward-fall preventive device beingswitched in the open state when the horizontal movement of said pushingdevice 23 brings at least the containers forward in the pushingdirection of said container group reach a position under said upperguide.

Some embodiments are characterized by a container group transportingmethod comprising providing a lift device for vertically stacking instages a plurality of container groups each including a plurality ofstanding containers arranged and collected in a horizontal direction,and carrying and elevating, stage by stage, said plurality of containergroups stacked vertically, horizontally pushing, with a pushing device,an uppermost container group elevated by said lift device by contactingsaid container group at one side thereof and moving horizontally towardthe other side to push said container group onto an airflow conveyerdisposed adjacent said lift device for receiving said uppermostcontainer group and transporting the container group horizontally, anddischarging said container group by opening a forward-fall preventivedevice switchable between a closed state for lying forwardly in apushing direction of said container group, as said pushing device moveshorizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of said container group when said container grouprides said airflow conveyer to enable a discharge of said containergroup for transport by said airflow conveyer, characterized in that saidcontainer group is discharged by freely varying a relative speed betweena transport speed of said airflow conveyer and a pushing speed of saidpushing device.

While reference numbers are set out as above for expediency ofcomparison to the drawings, such entry does not limit the presentinvention to the constructions shown in the accompanying drawings.

[Functions and Effects]

Certain embodiments of the invention are capable of varying thetransport functions.

That is, in a discharging step, a container group is discharged from thelift device onto the adjacent airflow conveyer. After discharging thecontainer group onto the airflow conveyer, the pushing device is movedback onto the lift device to receive a next container group, andreceives an uppermost container group elevated by the lift device. Thepushing device is moved horizontally onto the adjacent airflow conveyer.The forward-fall preventive device is switched to the open state. Theabove step is repeated. A non-feed time not feeding any containers occuruntil the next container group is discharged onto the airflow conveyer.Because of the non-feed time, an interruption could occur with thecontainers transported through the single-row transport path.

This non-feed time is further extended in an operation in which, afterdischarging a lowermost container on a pallet onto the airflow conveyer,an uppermost container on a next pallet is discharged onto the airflowconveyer.

In order to avoid the interruption occurring with the containerstransported through the single-row transport path, a sufficient numberof containers to be transported through the single-row transport pathwithin said non-feed time must be stored on the airflow conveyer orcontainer transport speed must be increased to prevent an interruptionof the containers transported through the single-row transport path.

Then, the present invention provides a speed varying mechanism forvarying a relative speed between the transport speed of the airflowconveyer and the pushing speed of the pushing device. As a transportingmethod for avoiding an interruption of the containers transportedthrough the single-row transport path, apart from a method fortransporting a container group in which the airflow conveyer and pushingdevice are movable at the same speed, a method may be employed fortransporting the containers in which the pushing speed of the pushingdevice is faster than the transport speed of the airflow conveyer.

Where, for example, containers such as short cans are transported withno upper guide disposed above the airflow conveyer, the transport speedof the airflow conveyer may be slowed in order to check tumbling of thecontainers on the airflow conveyer. Even so, by adjusting the speed offeeding container groups by the pushing device, a sufficient number ofcontainers may be secured on the airflow conveyer to avoid aninterruption of the containers transported through the single-rowtransport path.

Further, a method may be employed for transporting the containers inwhich the transport speed of the airflow conveyer is faster than thepushing speed of the pushing device.

Where, for example, containers such as long cans (or short cans) aretransported with an upper guide disposed above the airflow conveyer, thepushing speed of the pushing device may be slowed in order to dischargethe containers onto the airflow conveyer reliably without tumbling. Evenso, since the upper guide prevents tumbling of the containers, thetransport speed of the airflow conveyer may be adjusted to avoid aninterruption of the containers transported through the single-rowtransport path.

In addition, by employing the method for transporting the containers inwhich the transport speed of the airflow conveyer is faster than thepushing speed of the pushing device, the containers may be transportedin a rather loose state to reduce a contact pressure among thecontainers or by the pushing device. Damage to containers particularlyvulnerable to damage may be checked.

As a result, the container transporting equipment and the containertransporting method provided are capable of varying transport speedaccording to varied shapes the containers and equipment.

According to certain embodiments of the present invention, the transportspeed of the airflow conveyer and the pushing speed of the pushingdevice may be varied automatically.

A control device is provided for varying the transport speed of theairflow conveyer and the pushing speed of the pushing device. Forexample, by providing sensors for detecting presence or a mountingposition of the upper guide and for recognizing shapes such as sizes,intervals between, and tumbling of the containers transported,information may be transmitted to the control device for automaticallyvarying the transport speed of the airflow conveyer and the pushingspeed of the pushing device to a proper relative speed. Sensors may beprovided for detecting a state of the containers transported. Based oninformation transmitted from these sensors to the control device, thetransport speed of the airflow conveyer and the pushing speed of thepushing device may be varied automatically to a proper relative speed.

As a result, the container transporting equipment provided is capable ofautomatically varying container transport speed in accordance withvaried shapes of containers, installation, and transport conditions.

In certain embodiments, when the container group is discharged onto theairflow conveyer by opening the forward-fall preventive device during ahorizontal movement forwardly in the pushing direction of the pushingdevice, the containers may be discharged onto the airflow conveyer whilebeing in contact with one another.

In order to shorten the container discharging time, for example, it isconceivable to discharge the containers onto the airflow conveyer byopening the forward-fall preventive device during a horizontal movementforwardly in the pushing direction of the pushing device. However, alevel difference often occurs between the lift device and airflowconveyer when the container group is discharged from the lift deviceonto the airflow conveyer (the lift side being higher for the containersnot to be caught when discharged). By contacting preceding containers,the succeeding containers are less likely to tumble forward. Where, forexample, the transport speed of the airflow conveyer is set faster thanthe pushing speed of the pushing device, the container group may bedischarged onto the airflow conveyer by opening the forward-fallpreventive device during a horizontal movement forwardly in the pushingdirection of the pushing device. Then, when the containers at theforward end of the container group in the pushing device ride theairflow conveyer, those containers are transported fast by the airflowconveyer. This results in gaps formed with succeeding containers, hencea problem of the containers falling forward with ease.

However, in the present invention, the pushing speed of the pushingdevice is set faster than the transporting speed of the airflowconveyer. The containers at the forward end of the container group inthe pushing device are never transported fast by the airflow conveyereven when the forward-fall preventive device is opened during ahorizontal movement forwardly in the pushing direction of the pushingdevice. The containers may be discharged onto the airflow conveyer whilebeing in contact with one another.

As a result, the container transporting equipment provided is capable ofchecking a forward fall of the containers when the container group isdischarged from the lift device onto the airflow conveyer.

In preferred embodiments of the present invention, the containers may bedischarged from the lift device onto the airflow conveyer steadily andin a reduced time, and the containers discharged may be transported athigh speed.

Since forward-fall preventive device is switched to the open state asthe pushing device moves horizontally and forwardly in the pushingdirection on the airflow conveyer, the time spent to put theforward-fall preventive device in the open state may be included in thehorizontal moving time of the pushing device. This realizes a reductionin the container discharging time compared with the case of dischargingthe containers onto the airflow conveyer after ending the horizontalmovement of the pushing device onto the airflow conveyer.

When, for example, the containers are abruptly discharged to a positionof fast transport, the containers tumble easily owing to a difference inrelative speed. Where, as in the present invention, the transport speedof the airflow conveyer is the faster the farther forward in thetransporting direction, the containers may be discharged a position ofmoderate transport speed of the airflow conveyer, and the containersreceived may be transported at gradually increased speed. Thus, thecontainers may be discharged and transported steadily with little chanceof tumbling of the containers.

As a result, the container transporting equipment provided is capable ofimproving the container transport performance.

In certain embodiments, the present invention is capable of preventingtumbling of the containers discharged earlier.

That is, discharging onto the airflow conveyer of container groups bythe pushing device is performed in a discharging step repeated at fixedintervals to discharge the container group by opening the forward-fallpreventive device when the container group in the pushing device ridesthe airflow conveyer as the pushing device moves forward in the pushingdirection. When, for example, containers discharged at a precedingdischarging step remain in regions of opening of the forward-fallpreventive device under some circumstances (e.g. crowding and the likeof the containers transported), the containers present in the regions ofopening of the forward-fall preventive device would be knocked down bythe forward-fall preventive device opened in an opening operation.Further, there is a possibility of the tumbling of these containersknocking down adjacent containers one after another in chain action,thereby posing a problem.

However, in the present invention, detecting sensors are provided fordetecting the presence of the containers in the regions of opening ofthe forward-fall preventive device. When the detecting sensors detectthe presence of the container in the opening regions, the forward-fallpreventive device is maintained in the close state, thereby to avoid thecontainers being knocked down by the forward-fall preventive device inthe opening operation. When an absence of containers from the openingregions is detected, the forward-fall preventive device is opened andswitched to the open state for discharging the container group toexecute a normal step of discharging the container group.

As a result, the container transporting equipment provided is capable ofimproving the container transport performance.

According to certain embodiments of the present invention the containersmay be discharged onto the airflow conveyer without tumbling.

With the upper guide provided for preventing the containers tumblingduring transport by contacting the upper ends of the containers, where,for example, the container group is discharged by switching theforward-fall preventive device to the open state before reaching aposition under the upper guide, the containers could tumble beforereaching the position under the upper guide. In the present invention,the container group is discharged by switching the forward-fallpreventive device to the open state upon reaching the position under theupper guide. Thus, the containers may be discharged onto the airflowconveyer without tumbling.

As a result, the container transporting equipment provided is capable ofimproving the container transport performance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation of transporting equipment in one embodimentof the present invention;

FIG. 2 is a front view of a lift device according to the presentinvention;

FIG. 3 is an enlarged fragmentary view showing a separates sheetremoving device according to the present invention;

FIG. 4 is a schematic plan view showing a principal portion of thecontainer transporting equipment according to the present invention;

FIG. 5 is an explanatory functional view showing a mounting state of anupper guide according to the present invention;

FIG. 6 is an enlarged fragmentary view showing a mounting deviceaccording to the present invention;

FIG. 7 is an enlarged fragmentary explanatory functional view showing aforward-fall preventive device according to the present invention;

FIG. 8 is an enlarged fragmentary explanatory view showing a rotarydrive mechansim according to the present invention;

FIG. 9 is an explanatory view, partly in section, showing the rotarydrive mechansim according to the present invention;

FIG. 10 is an explanatory functional plan view showing a container grouptransfer mechanism according to the present invention;

FIG. 11 is an explanatory functional plan view showing the containergroup transfer mechanism according to the present invention;

FIG. 12 is an explanatory functional side view showing the containergroup transfer mechanism according to the present invention;

FIG. 13 is an explanatory functional side view showing the containergroup transfer mechanism according to the present invention;

FIG. 14 is a schematic plan view showing a principal portion ofcontainer transporting equipment in another embodiment;

FIG. 15 is an explanatory functional view showing container transportingequipment in a further embodiment;

FIG. 16 is an explanatory functional view of this application;

FIG. 17 is a forward-fall preventive device in a further embodiment;

FIG. 18 is a forward-fall preventive device in a further embodiment;

FIG. 19 is a view showing a conventional construction of a forward-fallpreventive device;

FIG. 20 is a view showing the conventional construction of theforward-fall preventive device;

FIG. 21 is a view showing a construction of a pivoting element; and

FIG. 22 is a view showing a modified example of pushing device.

BEST MODE FOR CARRYING OUT THE INVENTION

Container transporting equipment 1 in one embodiment of the presentinvention will be described hereinafter with reference to the drawings.

As shown in FIG. 1, the container transporting equipment 1 includes atransport conveyer 11 for transporting can group stacks 5 each includinga plurality of can groups 6 (one example of container groups 4)vertically stacked on a pallet 9, with separate sheets 8 interposed inbetween, each can group having a plurality of beer or soft drink cans 7(one example of containers 3) radially arranged and collected inupstanding posture; a lift device 14 for elevating, stage by stage, eachcan group stack 5 transported by the transport conveyer 11; an airflowconveyer 12 (one example of conveyer 17) disposed adjacent the liftdevice 14 for receiving an uppermost one of the can groups 6 elevated bythe lift device 14 and horizontally transporting the can group to a nextprocess; a container group transfer mechanism 2 (see FIG. 4) having apushing device 23 for contacting one side of the uppermost can group 6elevated by the lift device 14 and horizontally moving toward the otherside to push the can group 6 out onto the adjacent airflow conveyer 12,and a forward-fall preventive device 24 switchable between a closedstate for lying forwardly in a pushing direction of the can group 6, asthe pushing device 23 moves horizontally, to be capable of preventing aforward fall of cans 7, and an open state for opening a forward positionin the pushing direction of the can group 6 when the can group 6 ridesthe airflow conveyer 12 to enable a discharge of the can group 6; and apallet discharge conveyer 13 for discharging pallets 9 no longer neededafter discharging all can groups 6.

As shown in FIG. 2, said lift device 14 includes a lift deck 15 forsupporting each can group stack 5 transported by the transport conveyer11, and a lift deck moving mechanism 16 for vertically moving the liftdeck 15 such as by AC servomotor drive, for example, through gearengagement. In time of upward movement, the lift deck 15 is driven toelevate the can group stack 5 placed thereon, by degrees, one can group6 after another. The pallet 9 no longer needed after discharging all cangroups 6 is lowered and the pallet 9 is transferred to the palletdischarge conveyer 13 by a pallet transfer device not shown.

As shown in FIG. 16, a single row transport path is disposed at a rear,downstream end of said airflow conveyer, in the form of a funnel withtapering side wall plates of the transport path to feed one can afteranother to the next process.

As shown in FIGS. 12 and 13, this airflow conveyer 12 includes a deckplate 19 defining a plurality of air blowout bores 18, and a plate-likeupper guide 20 disposed above and parallel to the deck plate 19, in aposition 3 mm to 5 mm above the height of the cans. The cans 7 aretransported downstream in a somewhat floating fashion with air blownagainst the bottoms of cans 7 placed on the deck plate 19. Even when thecans start tumbling at this time, the tops thereof will contact theupper guide 20, whereby the cans 7 are prevented from tumbling. This isdue to no clearance being allowed between the cans 7 and upper guide 20.

As shown in FIG. 5, said upper guide 20 is supported by and fixed atside walls thereof to opposite side walls of the airflow conveyer 12 byair cylinders, not shown, erected in a plurality of locations along thetransport direction. The guide is switchable to a height matched to thecans 7 transported (long cans or short cans) in a one-touch operation ofa push-button switch to operate the air cylinders.

As shown in the right side of FIG. 5, for example, when transportinglow-height cans 7 a (short cans), the push-button switch is pressed tooperate the air cylinders in a one-touch operation to switch the upperguide 20 to a low set position to prevent tumbling of the low cans 7 a.

As shown in the left side of FIG. 5, when transporting high cans 7 a(long cans), the push-button switch is pressed to operate the aircylinders in a one-touch operation to switch the upper guide 20 to ahigh set position to prevent tumbling of the high cans 7 a.

As shown in FIGS. 4 and 6, said pushing device 23 includes a frame 26U-shaped in plan view and having three hold bars 25 arranged in threeinner positions and protrudable and retractable by air cylinders 34, anda frame moving mechanism 33 having engaging members 28 attached to aplurality of brackets 27 fixed below the frame 26 and engaged, supportedand guided by guide rails 29 attached to frame supporting side walls,and an arm extending laterally outward from an upper position of theframe 26 and gripping a belt 32 driven by a servomotor 31, therebyhorizontally moving the frame 26 forward and backward with forward andbackward movement of the belt 32 in the pushing direction of the cangroup 6.

As shown in FIG. 6, each said hold bars 25 has a bar member 36 formed ofa resin and fitted on a plate 35 attached to cylinder rods of the aircylinders 34. The cans 7 have a reduced chance of being damaged whencontacting the bar members 36.

Numeral 37 in FIG. 4 denotes slide shafts arranged at the right and leftsides of air cylinders 34 for guiding the hold bars 25 in the protrusionand retraction by the air cylinders 34 without causing complication.

As shown in FIG. 7, said forward-fall preventive device 24 includes apair of rotary drive mechanisms 38 for swing driving within apredetermined angular range, a turn element 40 pivotally connected to arotary shaft 39 of each rotary drive mechansim 38, and a gate member 41fixedly supported by the rotating member for contacting a forward end inthe pushing direction of the can group 6 to prevent a forward fall ofthe cans 7. The gate members 41 are driven by the rotary drivemechanisms 38 to swing open and close in double-door fashion.

At this time, the turn elements 40 have a short extending length to havethe centers of gravity located closer to the rotary shafts than thecenters of gravity of the gate members. This reduces the force ofinertia acting on the turn elements and gate members in a closingoperation, to decrease the impact of the gate members 41 contacting thecans 7 and check damage to the cans 7.

As shown in FIG. 8, said gate member 41 has a gate bar 60 formed ofpolyethylene resin (one example of elastic material 59) and engaged andsupported by a channel-shaped mount 61 attached to the turn element 40,in a position of the gate member 41 contacting the forward end in thepushing direction of can group 6. With this, the impact occurring intime of contact with the can group 6 may be absorbed by elasticdeformation of the polyethylene resin to check damage to the cans 7.

The gate member 41 undergoes severe damage or wear in positionscontacting can groups 6. The gate bar 60 engaged and supported by themount 61 may only be released and replaced with a new gate bar 60. Thisprovides for improved economy and efficiency of changing operation.

As shown in FIG. 9, said rotary drive mechansim 38 comprises aircylinders 42 with a pinion gear 39 a mounted on the rotary shaft 39,racks 43 a and 43 b formed on right and left pistons 43A and 43B,respectively, and engaged with the pinion gear 39 a. Air is suppliedinto and exhausted from cylinders 44 to move the pistons 43A and 43B.

The movement of the pistons 43A and 43B rotates the rotary shaft 39 toopen and close the turn element 40 and gate member 41 pivotallyconnected to the rotary shaft 39.

At this time, cushion rubber elements 46 a and 46 b (one example ofbuffer mechanism 45) are disposed at end surfaces in the respectivecylinders 44A and 44B. In time of an opening operation to the open stateto open a forward position in the pushing direction of can group 6 fordischarging the can group 6, an end surface of the piston 43A contactsthe cushion rubber 46 a. An elastic deformation of cushion rubber 46 aabsorbs the force of inertia occurring with the opening operation to acton the turn element 40 and gate member 41. In time of a closingoperation to the closed state for preventing a forward-fall of the cangroup 6, an end surface of piston 43B contacts the cushion rubber 46 b.An elastic deformation of cushion rubber 46 b absorbs the force ofinertia occurring with the closing operation to act on the turn element40 and gate member 41. This decreases the impact of the gate member 41contacting the cans 7 to check damage to the cans 7. (see FIG. 9)

Next, basic steps of transportation will be described following thetransport path of cans 7 based on the basic construction of theequipment described hereinbefore.

A) The transport conveyer 11 transports a can group stack 5 including aplurality of can groups 6 stacked on a pallet 9, onto the lift deck 15of lift device 14. The lift deck moving mechanism 16 is driven toelevate the can groups 6 in the can group stack 5 stage by stage, toload into the container group transfer mechanism 2 standing by above thelift device 14 (at startup of the container transporting equipment) withthe forward-fall preventive device 24 placed in the closed state. (seeFIGS. 10(a) and 12(a))

B) A separate sheet 8 placed on the uppermost can group 6 elevated bysaid lift device 14 is removed and transported by a separate sheetremoving and transporting device 47 disposed above the lift device 14 asshown in FIGS. 2 and 3.

Said separate sheet removing and transporting device 47 includesseparate sheet removing mechanisms 53 each having a vacuum head support49 with a plurality of vacuum heads 48 for supporting a separate sheet 8by suction, and a lift cylinder 50 for vertically moving the vacuum headsupport 49, i.e. a plurality of (two in this embodiment) first andsecond separate sheet removing mechanisms 53A and 53B mounted on amovable frame 52 movable along a guide rails 51.

To remove a separate sheet 8, the vacuum head support 49A of the firstseparate sheet removing mechanism 53A standing by above the lift device14 is lowered. After the separate sheet 8 placed on the uppermost cangroup 6 is suction-supported by the vacuum head 48, the vacuum headsupport 49A is raised and the movable frame 52 is moved horizontally toplace the first separate sheet removing mechanism 53A above a temporaryseparate sheet depot 54. The suction of vacuum head 48 is stopped totemporarily place the separate sheet 8 on the temporary separate sheettemporary depot 54.

Subsequently, the first separate sheet removing mechanism 53A is movedabove the lift device 14. (At this time, the second separates removingmechanism 53B lies above the temporary separate sheet depot 54.) Thevacuum head support 49A is lowered for the vacuum head 48 tosuction-support the separate sheet 8 placed on the uppermost can group6. The vacuum head support 49A is raised to remove the separate sheet 8from the can group 6. Simultaneously with this removing operation, thevacuum head support 49B of the second separate sheet removing mechanism53B is lowered to suction-support the separate sheet 8 temporarilyplaced on the temporary separate sheet depot 54. Then, the vacuum headsupport 49B is raised and the movable frame 52 is moved horizontally toplace the second separate sheet removing mechanism 53B above a dischargelift 55 for discharging separate sheets 8. The suction of vacuum head 48is stopped to drop the separate sheet 8 to the discharge lift 55. At thesame time, the first separate sheet removing mechanism 53A is placedabove the temporary separate sheet depot 54, the suction of vacuum head48 is stopped to temporarily place the separate sheet 8 on the temporaryseparate sheet depot 54.

The above steps are executed every time the can groups 6 are elevated byone stage by the lift device 14.

By employing the construction having the plurality of separate sheetremoving mechanisms 53 as noted above, the moving distance of theindividual separate sheet removing mechanisms 53 may be shortenedcompared with use of one separate sheet removing mechanism 53 forremoving separate sheets 8. This improves the separate sheet removingefficiency to improve the efficiency of transporting the can groups 6.

A pair of arms 57 are arranged opposite each other above said dischargelift 55 to be pivotable about axes by extension and contraction ofcylinders 56. The separate sheets 8 dropped to the discharge lift 55 areonce placed on the arms 57 until the sheets reaches a certain number,and then the cylinders 56 are contracted to swing the arms 57 downwardto drop the separate sheets 8 placed on the arms 57 to the dischargelift 55. The discharge lift 55 is lowered to discharge the separatesheets 8. The separate sheets 8 are once placed on the arms 57 in orderto save time taken by the operation of the discharge lift 55 fordischarging the separate sheets 8. In other words, this is done in orderto avoid the discharge operation retarding the operation to remove theseparate sheets 8.

C) Simultaneously with the operation to remove the separates sheet 8 onsaid can group 6, the air cylinders 34 are extended to place the holdbars 25 in contact with the rear end in the pushing direction and theopposite sides of the can group 6 to hold the can group 6 in the frame26 of the container group transfer mechanism 2. (The forward end of thecan group 6 is in contact with the gate members 41.) The frame 26 ismoved horizontally toward the airflow conveyer 12 by the belt drive ofthe servomotor 31 included in the frame moving mechanism 33. (see FIGS.10(a) and 12(a))

In anticipation of ends of the separate sheet 8 being bent upward ordownward, the can group 6 elevated by the lift device 14 is stoppedslightly above a bridge plate 58 disposed between the airflow conveyer12 and lift device 14. Thus, when the cans 7 move from the lift device14 to the bridge plate 58, the cans 7 could tilt and fall forwardeasily. However, with the gate members 41 holding the forward positionof the can group 6, the cans may be discharged to the airflow conveyer12 without tumbling. (see FIG. 12)

In this embodiment, an example is described as having the bridge plate58 disposed between the airflow conveyer 12 and lift device 14 todischarge the can group 6 to the airflow conveyer 12. The discharge maybe effected directly from the lift device 14 to the airflow conveyer 12without using the bridge plate 58.

The above are the basic operating steps of this equipment. In thisequipment, a relative speed between the airflow conveyer 12 and pushingdevice 23 is arranged variable by a speed varying mechanism 62.

As shown in FIG. 4, said speed varying mechanism 62, for example,includes a wind force switching device 64 for switching the degree ofwind force of a blower 63, and a change speed device 65 for changing thedriving speed of the servomotor 31. Said wind force switching device 64is operable to vary the rate of air blowout from the air blowout bores18, thereby to vary the speed of transporting the cans 7 by the airflowconveyer 12. Said change speed device 65 is operable to vary the drivingspeed of the belt 32, thereby to vary the speed of transporting the cans7 by the pushing device 23. Thus, the transport speed of the airflowconveyer 12 and the transport speed of the pushing device 23 may bevaried separately.

It is therefore possible to equalize the transport speed of the airflowconveyer 12 and the pushing speed of the pushing device 23, of course.The pushing speed of the pushing device 23 may be set faster than thetransport speed of the airflow conveyer 12, or the transport speed ofthe airflow conveyer 12 may be set faster than the pushing speed of thepushing device 23. In this way, the transport function may be varied tosuit a transport mode. (see FIG. 4)

As one mode of implementation thereof, for example, the can group 6 heldin said frame 26 rides the airflow conveyer 12, with the pushing speedof the pushing device 23 set faster than the transport speed of theairflow conveyer 12. An operation is started to open the turn elements40 and gate members 41, opening a forward position in the pushingdirection of can group 6, to move the can group horizontally on theairflow conveyer 12 forward in the pushing direction. The leading cans 7of the can group 6 in the frame 26 are never transported faster than theothers by the airflow conveyer 12 set slower than the pushing device 23.Thus, the cans 7 may be discharged as maintained in contact with oneanother onto the airflow conveyer 12 to be transported downstream. (seeFIGS. 10(b) and 12(b))

At this time, where the turn elements 40 and gate members 41 areswitchable open to discharge the can group upon reaching a positionbelow the upper guide 20 disposed above the airflow conveyer 12, theupper guide 20 can contact the upper end of the can group 6 to prevent atumbling of the cans 7, thereby enabling a discharge to the airflowconveyer 12 free of a tumbling of the can group 6.

D) After the can group 6 is discharged to the airflow conveyer 12, abackward movement is made onto the lift device 14 with an operationstarted to close the turn elements 40 and gate members 41 and whileretracting the hold bars 25. (see FIGS. 11(a) and 13(a))

Then, a can group 6 in the next stage elevated by the lift deck movingmechanism 16 is loaded into the container group transfer mechanism 2.(see FIGS. 11(b) and 13(b))

Thereafter the steps from FIGS. 11(b) to 13(b) are repeated until thecan groups 6 are emptied from the pallet 9.

By the time the container group transfer mechanism 2 is brought backonto the lift device 14, a separates sheet 8 remaining on a next cangroup 6 is removed by the separates sheet removing and transportingdevice 47.

E) When all can groups 6 have been emptied from the pallet 9, the liftdeck 15 is lowered. A pallet transfer device not shown transfers thepallet from inside the lift device 14 toward the pallet dischargeconveyer 13. Subsequently, the operations of A) et seq are repeated.

[Other Embodiments]

Other embodiments will be described hereinafter.

<1> The foregoing embodiment has been described in relation to thecontainer transporting equipment having a speed varying mechanism forvarying a relative speed between the transport speed of the airflowconveyer and the pushing speed of the pushing device. As shown in FIG.14, a control device 66 may be provided for varying the transport speedof the airflow conveyer 12 and the pushing speed of the pushing device23.

With this, for example, the rate of air blowout from the air blowoutbores 18 and the driving speed of the belt 32 by the servomotor 31 maybe varied automatically. For example, by providing a sensor not shownfor detecting presence or a mounting position of the upper guide 20 anda sensor capable of recognizing shapes such as sizes of containers 3transported, the transport speed of the airflow conveyer 12 and thepushing speed of the pushing device 23 may be varied automatically to aproper relative speed based on information from these sensors even whenthe mounting state of the upper guide 20 and the shape of containers 3transported change. Further by providing a sensor or the like fordetecting a transporting state of containers 3, the two speeds may bevaried according to the transporting state of containers 3 (e.g.crowding and the like of the containers transported).

<2> In the foregoing embodiment, the case of setting the pushing speedof the pushing device faster than the transport speed of the airflowconveyer has been described. As the pushing device moves horizontallyforward in the pushing direction on the airflow conveyer, theforward-fall preventive device may be switched to the open state, andthe transport speed of the airflow conveyer may be increased the furtherforward in the direction of transporting the containers. Specifically,the rate of air blowout from the air blowout bores may be set low wherethe containers are received from the pushing device, and the higher thefarther away in the transporting direction from the receiving position.

With this arrangement, the time spent to put the forward-fall preventivedevice in the open state may be included in the horizontal moving timeof the pushing device. This realizes a reduction in the containerdischarging time compared with the case of discharging the containersonto the airflow conveyer after ending the horizontal movement of thepushing device onto the airflow conveyer.

When, for example, the containers are abruptly discharged to a positionof fast transport, the containers tumble easily owing to a difference inrelative speed. Where, as in the above arrangement, the transport speedof the airflow conveyer is the faster the farther forward in thetransporting direction, the containers may be discharged to a positionof moderate transport speed of the airflow conveyer, and the containersreceived may be transported at gradually increased speed. Thus, thecontainers may be discharged and transported steadily with little chanceof tumbling of the containers.

<3> As shown in FIG. 15, detecting sensors 67 may be provided fordetecting presence of containers 3 in regions 69 where an openingoperation of the forward-fall preventive device 24 takes place. Acontrol device 68 may be provided for maintaining the forward-fallpreventive device 24 in the closed state when the detecting sensors 67detect the containers 3 present in the opening regions 69, even if thecontainer group 4 is brought by the pushing device 23 onto the airflowconveyer 12, and for switching the forward-fall preventive device 24 tothe open state for discharging the container group 4 when an absence ofcontainers 3 is detected.

With this, even if containers 3 discharged at a discharging step of apreceding container group 4 remain in the regions of opening of theforward-fall preventive device 24 under some circumstances, the presenceof the containers 3 is detectable by the detecting sensors 67. When thedetecting sensors 67 detect the presence of the container 3 in theopening regions, the forward-fall preventive device 24 is maintained inthe close state, thereby to avoid the containers 3 being knocked down bythe forward-fall preventive device 24 in the opening operation.

<4> In the foregoing embodiment, the gate bars are described as beingformed of polyethylene resin. The gate bars are not limited to beingformed of polyethylene resin, but may be formed of an elastic materialother than polyethylene resin or elastic rubber.

The gate bars may be formed of a material other than an elastic materialsuch as metal or non-elastic resin. The above construction is applicablealso to the hold bars 25.

<5> The forward-fall preventive device 24 is not limited to theconstruction for laterally opening and closing in double-door fashion asdescribed in the foregoing embodiment. As shown in FIG. 17, for example,flexible slide members 230 may be arranged extendible and retractable ina channel-shaped pushing device 23 to switch between a closed stateprojecting from opposite opening ends of the pushing device 23 forpreventing a forward fall of cans 7, and an open state retracted intothe pushing device 23 for opening a forward area for allowing theconveyor to transport a can group 4.

Further, instead of being slidable into the pushing device 23, the slidemembers may be slidable to project left and right from the pushingdevice 23 to provide the open state.

<6> The forward-fall preventive device 24 is not limited to theconstruction having a pair of right and left turn elements and gatemembers as described in the foregoing embodiment. As shown in FIG. 18,for example, one plate 232 may be attached through a pivotal axis 231disposed at one of the opening ends of the pushing device 23 to beswitchable between a closed state for preventing a forward fall of cans,and an open state for opening a forward area for allowing the conveyorto transport a can group 4. Though not shown, one slide member may beprovided at one of the opening ends of the pushing device 23 to beswitchable between a closed state for preventing a forward fall of cans,and an open state with the slide member slid laterally of the pushingdevice 23 for opening a forward area for allowing the conveyor totransport a can group 4.

<7> The pushing device 23 is not limited to the channel shape asdescribed in the foregoing embodiment. As shown FIG. 22, for example, apushing plate 23A may extend perpendicular to the moving direction forcontacting the rear end, in the moving direction of the conveyer, of atube group 6 and pushing it to a receiving portion 58 of the conveyer,with a plurality of guides 23B formed of bars disposed at oppositesides. While the guides 23B prevent the can group 6 displacinglaterally, the pushing plate 23A moves horizontally to deliver the cangroup 6 to the receiving portion 58.

<8> The foregoing embodiment has been described as having the buffermechanism 45 disposed on one end surface of cylinder 44 as shown in FIG.9. For example, the buffer mechanism 45 such as cushion rubber may bedisposed on one end surface of each piston 43A.

The position of the buffer mechanism is not limited to the interior ofthe air cylinder. The buffer mechanism may be disposed in positions forcontacting the turn elements in the open state and close state forabsorbing the force of inertia of the turn elements and gate members inan inertial swing.

<9> In the foregoing embodiment, the rotary drive mechansim is in theform of an air cylinder. The rotary drive mechansim is not limited tothe air cylinder, but may use a varied motor.

INDUSTRIAL UTILITY

The present invention provides container transporting equipmentincluding a lift device for vertically stacking in stages a plurality ofcontainer groups each including a plurality of standing containersarranged and collected in a horizontal direction, and carrying andelevating, stage by stage, said plurality of container groups stackedvertically, provides an air conveyer adjacent the lift device forreceiving an uppermost container group elevated by the lift device andtransporting the container group horizontally, a pushing device forpushing the uppermost container group onto the adjacent airflow conveyerby contacting the container group at one side thereof and movinghorizontally toward the other side, and a forward-fall preventive deviceswitchable between a closed state for lying forwardly in a pushingdirection of the container group, as the pushing device moveshorizontally, to be capable of preventing a forward fall of containers,and an open state for opening a forward position in the pushingdirection of the container group when the container group rides theairflow conveyer to enable a discharge of the container group, totransport the container group effectively.

1. A container group transfer mechanism comprising a pushing device forhorizontally pushing a container group including a plurality of standingcontainers arranged and collected in a horizontal direction, bycontacting said container group at one side thereof and movinghorizontally toward the other side, and a forward-fall preventive devicefor contacting a forward end in a pushing direction of said containergroup and switchable between a closed state for lying forwardly in thepushing direction of said container group, as said pushing device moveshorizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of said container group to enable a discharge of thecontainer group, wherein said forward-fall preventive device has alateral extension and maintains horizontal posture throughout itsmovement between the closed state and the open state.
 2. Containertransporting equipment comprising a lift device for vertically stackingin stages a plurality of container groups each including a plurality ofstanding containers arranged and collected in a horizontal direction,and carrying and elevating, stage by stage, said plurality of containergroups stacked vertically, a conveyer disposed adjacent said lift devicefor receiving an uppermost container group elevated by said lift deviceand transporting the container group horizontally, and a container grouptransfer mechanism having a pushing device for pushing said uppermostcontainer group onto said conveyer by contacting said container group atone side thereof and moving horizontally toward the other side, and aforward-fall preventive device switchable between a closed state forlying forwardly in a pushing direction of said container group, as saidpushing device moves horizontally, to be capable of preventing a forwardfall of said containers, and an open state for opening a forwardposition in the pushing direction of said container group when saidcontainer group rides said conveyer to enable a discharge of saidcontainer group, wherein said forward-fall preventive device islaterally switchable.
 3. Container transporting equipment as defined inclaim 2, wherein said conveyer is an airflow conveyer.
 4. A containergroup transfer method comprising horizontally pushing, with a pushingdevice, a container group including a plurality of standing containersarranged and collected in a horizontal direction, by contacting saidcontainer group at one side thereof and moving horizontally toward theother side, and discharging the container group by opening aforward-fall preventive device for contacting a forward end in a pushingdirection of said container group and switchable between a closed statefor lying forwardly in the pushing direction of said container group, assaid pushing device moves horizontally, to be capable of preventing aforward fall of said containers, and an open state for opening a forwardposition in the pushing direction of said container group to enable adischarge of the container group, wherein said container group isdischarged by laterally opening said forward-fall preventive device,wherein said free-fall preventive device has a lateral extension andmaintains horizontal posture throughout its movement between the closedstate and the open state.
 5. A container group transporting methodcomprising vertically stacking in stages a plurality of container groupseach including a plurality of standing containers arranged and collectedin a horizontal direction, and carrying and elevating, stage by stage,with a lift device, said plurality of container groups stackedvertically, horizontally pushing, with a pushing device, an uppermostcontainer group elevated by said lift device by contacting saidcontainer group at one side thereof and moving horizontally toward theother side to push said container group onto a conveyer disposedadjacent said lift device for receiving said uppermost container groupand transporting the container group horizontally, and discharging saidcontainer group by opening a forward-fall preventive device switchablebetween a closed state for lying forwardly in a pushing direction ofsaid container group, as said pushing device moves horizontally, to becapable of preventing a forward fall of said containers, and an openstate for opening a forward position in the pushing direction of saidcontainer group when said container group rides said conveyer to enablea discharge of said container group, wherein said container group isdischarged by laterally opening said forward-fail preventive device. 6.A container group transporting method as defined in claim 5, whereinsaid conveyer is an airflow conveyer.
 7. A container group transfermechanism comprising a pushing device for horizontally pushing acontainer group including a plurality of standing containers arrangedand collected in a horizontal direction, by contacting said containergroup at one side thereof and moving horizontally toward the other side,and a forward-fall preventive device for lying forwardly in a pushingdirection of said container group, as said pushing device moveshorizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of said container group to enable a discharge of thecontainer group, wherein said forward-fall preventive device includesturn elements connected for pivotal movement about rotary shafts, rotarydrive mechanisms for swinging said turn elements within a predeterminedangular range, and gate members fixedly supported by said turn elementsfor contacting a forward end in a pushing direction of said containergroup to be capable of preventing a forward fall of the containers, saidturn elements being formed to have centers of gravity located closer tosaid rotary shafts than centers of gravity of said gate members.
 8. Acontainer group transfer mechanism as defined in claim 7, wherein saidforward-fall preventive device includes buffer mechanisms for absorbinginertial swinging of said gate members.
 9. A container group transfermechanism as defined in claim 7, wherein said rotary drive mechanismsare formed of air cylinders.
 10. A container group transfer mechanism asdefined in claim 7, wherein said gate members have elastic materials 59provided in positions contactable with the forward end in the pushingdirection of said container group.
 11. Container transporting equipmentcomprising a lift device for vertically stacking in stages a pluralityof container groups each including a plurality of standing containersarranged and collected in a horizontal direction, and carrying andelevating, stage by stage, said plurality of container groups stackedvertically, an air conveyer disposed adjacent said lift device forreceiving an uppermost container group elevated by said lift device andtransporting the container group horizontally, a pushing device forpushing said uppermost container group onto said airflow conveyer bycontacting said container group at one side thereof and movinghorizontally toward the other side, and a forward-fall preventive deviceswitchable between a closed state for lying forwardly in a pushingdirection of said container group, as said pushing device moveshorizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of said container group when said container grouprides said airflow conveyer to enable a discharge of said containergroup herein said container transporting equipment comprises a speedvarying mechanism for varying a relative speed between a transport speedof said airflow conveyer and a pushing speed of said pushing device. 12.Container transporting equipment as defined in claim 11, comprising acontrol device for automatically varying the transport speed of saidairflow conveyer and the pushing speed of said pushing device. 13.Container transporting equipment as defined in claim 11, wherein thepushing speed of said pushing device is set faster than the transportspeed of said airflow conveyer.
 14. Container transporting equipment asdefined in claim 11, wherein, as said pushing device moves horizontallyforward in the pushing direction on said airflow conveyer, saidforward-fall preventive device is switched to the open state, and thetransport speed of said airflow conveyer is increased the furtherforward in the direction of transporting the containers.
 15. Containertransporting equipment as defined in claim 11, comprising an upper guidedisposed above said airflow conveyer for contacting upper ends of thecontainers to prevent tumbling of the containers being transported, saidforward-fall preventive device being switched in the open state when thehorizontal movement of said pushing device brings at least thecontainers forward in the pushing direction of said container groupreach a position under said upper guide.
 16. Container transportingequipment comprising a lift device for vertically stacking in stages aplurality of container groups each including a plurality of standingcontainers arranged and collected in a horizontal direction, andcarrying and elevating, stage by stage, said plurality of containergroups stacked vertically, an air conveyer disposed adjacent said liftdevice for receiving an uppermost container group elevated by said liftdevice and transporting the container group horizontally, a pushingdevice for pushing said uppermost container group onto said airflowconveyer by contacting said container group at one side thereof andmoving horizontally toward the other side, and a forward-fall preventivedevice switchable between a closed state for lying forwardly in apushing direction of said container group, as said pushing device moveshorizontally, to be capable of preventing a forward fall of saidcontainers, and an open state for opening a forward position in thepushing direction of said container group when said container grouprides said airflow conveyer to enable a discharge of said containergroup, wherein said container transporting equipment comprises detectingsensors for detecting presence of containers in regions where an openingoperation of said forward-fall preventive device takes place, and acontrol device for maintaining said forward-fall preventive device inthe closed state when said detecting sensors detect the containerspresent in the regions of opening, even if said container group isbrought by said pushing device onto said airflow conveyer, and forswitching said forward-fall preventive device to the open state fordischarging said container group when an absence of containers isdetected.
 17. A container group transporting method comprising providinga lift device for vertically stacking in stages a plurality of containergroups each including a plurality of standing containers arranged andcollected in a horizontal direction, and carrying and elevating, stageby stage, said plurality of container groups stacked vertically,horizontally pushing, with a pushing device, an uppermost containergroup elevated by said lift device by contacting said container group atone side thereof and moving horizontally toward the other side to pushsaid container group onto an airflow conveyer disposed adjacent saidlift device for receiving said uppermost container group andtransporting the container group horizontally, and discharging saidcontainer group by opening a forward-fall preventive device switchablebetween a closed state for lying forwardly in a pushing direction ofsaid container group, as said pushing device moves horizontally, to becapable of preventing a forward fall of said containers, and an openstate for opening a forward position in the pushing direction of saidcontainer group when said container group rides said airflow conveyer toenable a discharge of said container group for transport by said airflowconveyer, wherein said container group is discharged by freely varying arelative speed between a transport speed of said airflow conveyer and apushing speed of said pushing device.